How do I check Data Guard apply lag?

Query V$DATAGUARD_STATS and review the Apply Lag value.

How do I check Data Guard transport lag?

Query V$DATAGUARD_STATS and review the Transport Lag value.

How do I detect archive gaps?

Use SELECT * FROM V$ARCHIVE_GAP.

What is RMAN Backup Validation?

RMAN Backup Validation verifies Oracle backup integrity and recoverability without performing a restore.

What does RESTORE DATABASE VALIDATE do?

It verifies that RMAN backups can be restored successfully without actually restoring files.

How do I detect Oracle block corruption?

Use V$DATABASE_BLOCK_CORRUPTION and RMAN VALIDATE DATABASE CHECK LOGICAL.

What are the most important Oracle DBA interview topics?

Oracle Architecture, RMAN, Backup and Recovery, Data Guard, RAC, Performance Tuning, Security, and Troubleshooting are the most important Oracle DBA interview topics.

Is Oracle DBA still a good career in 2026?

Yes. Oracle DBA remains a strong career path due to the widespread use of Oracle databases in enterprise environments.

What Oracle version should I learn in 2026?

Oracle 19c and Oracle 23ai are the most valuable Oracle database versions to learn in 2026.

What does ORA-01034 ORACLE Not Available mean?

ORA-01034 indicates that the Oracle database instance is unavailable because it is not started, cannot be accessed, or failed during startup.

How do I fix ORA-01034?

Verify ORACLE_HOME and ORACLE_SID, review the Alert Log, check listener status, confirm background processes are running, and start the database using SQL*Plus as SYSDBA.

Why does ORA-27101 appear with ORA-01034?

ORA-27101 usually occurs when Oracle cannot locate the shared memory for the specified database instance because the database is not running or the environment variables are incorrect.

REP-0501 ORA-01017 unable to connect to the specified database

Applies to:

Enterprise Linux Version 5.7

Database 11gR2

Oracle Forms/Reports 6i

Description:

We have an in-house developed application on Oracle Form/Reports 6i with Oracle Database 9.2 32bit on Windows Server 2008 32bit. Application is working fine. I have assigned a task from my manager to upgrade the database and also migrate the database server on Linux. I have done all the activities successfully. After that, Application is working fine except reports. When I run any report from application the report engine log give me the following error:

REP-0501: Unable to connect to the specified database.
ORA-01017: invalid username/password; logon denied

Solution:

After some research work I have found the following solution:

If you have recently created an 11g database, one behavior change that you may find confusing is that passwords are now case-sensitive by default. This behavior is controlled by the SEC_CASE_SENSITIVE_LOGON parameter.

Check the current value of above parameter:

SQL> connect system/oracle
Connected.
SQL> show parameter sec_case_sensitive_logon
NAME TYPE VALUE
------------------------ ------- -----
sec_case_sensitive_logon boolean TRUE

Default value of this parameter is TRUE, change it to FALSE. After restart the database reports are working fine without any error.

👉 Check our complete guide: Oracle Error Codes Guide

Author Box

About the Author

Rana Abdul Wahid is an experienced Oracle Database Administrator with expertise in Oracle Database Administration, Oracle Data Guard, RMAN Backup & Recovery, Oracle RAC, Oracle E-Business Suite, Performance Tuning, and High Availability Solutions.

Through this blog, he shares practical Oracle DBA solutions, troubleshooting guides, interview preparation resources, and production-tested best practices for database professionals worldwide.

6 comments:

AnonymousNovember 24, 2014 at 5:17:00 PM GMT+5
Thanks a lot for the Solution, Worked like a charm!!!!
mickeyMay 3, 2020 at 1:39:00 AM GMT+5
Thanks for the solution
mdOctober 10, 2020 at 12:43:00 PM GMT+5
Thanks for sharing this great information I am impressed by the information that you have on this blog. Same as your blog i found another one Oracle Fusion Financials , Oracle Project Portfolio Management (PPM) Cloud Tutorial and Oracle Fusion Procurement . Actually I was looking for the same information on internet for Oracle Fusion Manufacturing , Oracle APEX , Oracle Financials Cloud and came across your blog. I am impressed by the information that you have on this blog. It shows how well you understand this subject, you can check more aboutOracle Fusion Supply Chain Management Cloud , Oracle HCM Cloud , Oracle Project Portfolio Management (PPM) Cloud , Oracle Cloud Applications to better understand

amNovember 17, 2020 at 3:07:00 PM GMT+5
I wish to show thanks to you just for bailing me out of this particular trouble. As a result of checking through the net and meeting techniques that were not productive, Same as your blog I found another one Oracle Cloud Applications .Actually I was looking for the same information on internet for Oracle Cloud Applications Consultant and came across your blog. I am impressed by the information that you have on this blog. Thanks once more for all the details.
UnknownMarch 6, 2021 at 10:59:00 PM GMT+5

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